drm/lima: separate clk/regulator enable/disable function

For being used by both device init/fini and suspend/resume.
Tested-by: Bhushan Shah <bshah@kde.org>
Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200421133551.31481-9-yuq825@gmail.com

drivers/gpu/drm/lima/lima_device.c

@@ -81,6 +81,44 @@ const char *lima_ip_name(struct lima_ip *ip)
 	return lima_ip_desc[ip->id].name;
 }
 
+static int lima_clk_enable(struct lima_device *dev)
+{
+	int err;
+
+	err = clk_prepare_enable(dev->clk_bus);
+	if (err)
+		return err;
+
+	err = clk_prepare_enable(dev->clk_gpu);
+	if (err)
+		goto error_out0;
+
+	if (dev->reset) {
+		err = reset_control_deassert(dev->reset);
+		if (err) {
+			dev_err(dev->dev,
+				"reset controller deassert failed %d\n", err);
+			goto error_out1;
+		}
+	}
+
+	return 0;
+
+error_out1:
+	clk_disable_unprepare(dev->clk_gpu);
+error_out0:
+	clk_disable_unprepare(dev->clk_bus);
+	return err;
+}
+
+static void lima_clk_disable(struct lima_device *dev)
+{
+	if (dev->reset)
+		reset_control_assert(dev->reset);
+	clk_disable_unprepare(dev->clk_gpu);
+	clk_disable_unprepare(dev->clk_bus);
+}
+
 static int lima_clk_init(struct lima_device *dev)
 {
 	int err;
@@ -90,6 +128,7 @@ static int lima_clk_init(struct lima_device *dev)
 		err = PTR_ERR(dev->clk_bus);
 		if (err != -EPROBE_DEFER)
 			dev_err(dev->dev, "get bus clk failed %d\n", err);
+		dev->clk_bus = NULL;
 		return err;
 	}
 
@@ -98,49 +137,48 @@ static int lima_clk_init(struct lima_device *dev)
 		err = PTR_ERR(dev->clk_gpu);
 		if (err != -EPROBE_DEFER)
 			dev_err(dev->dev, "get core clk failed %d\n", err);
+		dev->clk_gpu = NULL;
 		return err;
 	}
 
-	err = clk_prepare_enable(dev->clk_bus);
-	if (err)
-		return err;
-
-	err = clk_prepare_enable(dev->clk_gpu);
-	if (err)
-		goto error_out0;
-
 	dev->reset = devm_reset_control_array_get_optional_shared(dev->dev);
-
 	if (IS_ERR(dev->reset)) {
 		err = PTR_ERR(dev->reset);
 		if (err != -EPROBE_DEFER)
 			dev_err(dev->dev, "get reset controller failed %d\n",
 				err);
-		goto error_out1;
-	} else if (dev->reset != NULL) {
-		err = reset_control_deassert(dev->reset);
-		if (err) {
-			dev_err(dev->dev,
-				"reset controller deassert failed %d\n", err);
-			goto error_out1;
-		}
+		dev->reset = NULL;
+		return err;
 	}
 
+	return lima_clk_enable(dev);
+}
+
+static void lima_clk_fini(struct lima_device *dev)
+{
+	lima_clk_disable(dev);
+}
+
+static int lima_regulator_enable(struct lima_device *dev)
+{
+	int ret;
+
+	if (!dev->regulator)
 		return 0;
 
-error_out1:
-	clk_disable_unprepare(dev->clk_gpu);
-error_out0:
-	clk_disable_unprepare(dev->clk_bus);
-	return err;
+	ret = regulator_enable(dev->regulator);
+	if (ret < 0) {
+		dev_err(dev->dev, "failed to enable regulator: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
 }
 
-static void lima_clk_fini(struct lima_device *dev)
+static void lima_regulator_disable(struct lima_device *dev)
 {
-	if (dev->reset != NULL)
-		reset_control_assert(dev->reset);
-	clk_disable_unprepare(dev->clk_gpu);
-	clk_disable_unprepare(dev->clk_bus);
+	if (dev->regulator)
+		regulator_disable(dev->regulator);
 }
 
 static int lima_regulator_init(struct lima_device *dev)
@@ -158,19 +196,12 @@ static int lima_regulator_init(struct lima_device *dev)
 		return ret;
 	}
 
-	ret = regulator_enable(dev->regulator);
-	if (ret < 0) {
-		dev_err(dev->dev, "failed to enable regulator: %d\n", ret);
-		return ret;
-	}
-
-	return 0;
+	return lima_regulator_enable(dev);
 }
 
 static void lima_regulator_fini(struct lima_device *dev)
 {
-	if (dev->regulator)
-		regulator_disable(dev->regulator);
+	lima_regulator_disable(dev);
 }
 
 static int lima_init_ip(struct lima_device *dev, int index)